Drive Device and Valve Comprising the Same

ABSTRACT

The invention relates to a drive device and a valve comprising the drive device; the drive device senses the pressure of the working medium and generates the drive force to control the flow of the working medium; the drive device comprises a sensing part with a chamber and a drive shaft; vents and an air exhausting device are arranged on the chamber. The drive device and the valve comprising the drive device in the invention can exhaust air entering the chamber along the working medium out of the chamber by the vents on the chamber; and it optimizes the performance of the drive device and the valve and keeps the work stability.

TECHNICAL FIELD

The invention relates to a drive device for sensing medium pressure and a valve comprising the drive device.

BACKGROUND ART

At present, the drive device and valve comprising the drive device, such as actuator and adjusting valve comprise a sealing chamber; when the working medium is charged in the chamber, the air in the working medium can enter the chamber; it always exists the state of mixing the air and the working medium is in the chamber; if the working medium is the liquid, the compressed air and uncompressed liquid exit in the drive device together. Although the drive device can work, it is not stable.

Specifically, the valve as shown in FIG. 1, the valve 1 comprises a drive device 10; a sensing chamber 13 is formed by the shell 11 and the membrane 12 of the drive device; the membrane 12 is connected with the drive shaft 14; the membrane 12 can sense the pressure in the chamber and drive the drive shaft 14; the drive shaft 14 further drives the valve core component 15 to control the working medium. When the air in the working medium enters the valve, the working medium can enter the sealed chamber of the drive device so that the air in the chamber cannot be discharged; it is always the mixed state of air and working medium in the chamber; the greater of the volume of the chamber, the more of the air, which results it has smaller and smaller space of the working medium held in the chamber; the capacity of the working medium in the chamber is small, so the pressure of working medium sensed by the membrane is not accurate, which results the valve is not stable.

CONTENT OF INVENTION

The invention provides a drive device and a valve comprising the drive device; and it solves the unstable problem of drive device and valve.

On one hand, the example of the invention provides a drive device for sensing the pressure of the working medium and generating the drive force to control the flow of the working medium; the drive device comprises a sensing part which comprises a chamber and a sensing device located in or above the chamber; there are vents on the chamber; a drive shaft which passes through the chamber; one end of the drive shaft is connected with the sensing device which senses the pressure of the working medium and drives the drive shaft to move.

The chamber of the drive device comprises a shell and a membrane; the membrane is the sensing device; the membrane is connected with the drive shaft; the working medium communicates with the shell and enters the chamber; and the membrane senses the pressure change of the working medium and drives the drive shaft to move.

There are vents on the chamber of the drive device of the invention, which discharge the air entering the chamber along with the working medium to improve the stability of the drive device. The drive device provided in the invention can be used in different devices, such as valve, all kind of regulator and the like to control or adjust the pressure or flow of the working medium.

On the other hand, the invention provides a valve which is connected with the main fluid pipeline and adjusts the pressure in the main pipeline; the valve comprises a drive device and a valve; the drive device is connected with the valve; the valve comprises an inlet chamber and an outlet chamber; the inlet chamber is connected with the upstream pipeline of the main pipeline and the outlet chamber is connected with the downstream pipeline of the main pipeline; a flow control device is arranged between the inlet chamber and the outlet chamber; the flow control device controls the flow of the working medium in the control valve; the drive device comprises a sensing chamber and a drive shaft; the sensing chamber is composed of the membrane and the shell; the membrane is connected with one end of the drive shaft and capable of sensing the pressure of the sensing chamber and driving the drive shaft to move; there are vents on the shell; and the other end of the drive shaft of the drive device is connected with the flow control device.

The shell of the sensing chamber of the valve is provided with a first connecting pipeline; and the vents are located above the connection position of the first connecting pipeline and the shell in the vertical direction.

The first connecting pipeline of the valve is arranged between the shell and the downstream pipeline of the main pipeline; a second connecting pipeline is arranged between the vent and the downstream pipeline of the main pipeline; and the connection position of the second connecting pipeline and the downstream pipeline of the main pipeline is located at the downstream of the connection part of the first connecting pipeline and the downstream pipeline of the main pipeline.

The first connecting pipeline of the valve is arranged between the shell and the upstream pipeline of the main pipeline; the second connecting pipeline is arranged between the vent and the upstream pipeline of the main pipeline; and the connection position of the second connecting pipeline and the upstream pipeline of the main pipeline is located at the downstream of the first connecting pipeline and the upstream pipeline of the main pipeline.

The vents of the valve are connected with the air exhausting device which controls the gas discharged from the sensing chamber.

The air exhausting device of the valve is bulkhead or vent valve.

The flow control device of the valve is the valve clack which is arranged at the end of the drive shaft; the valve further comprises a valve opening arranged in the valve; the valve opening is arranged between the inlet chamber and the outlet chamber; the valve clack matches with the valve opening; and along with the movement of the drive shaft, the valve clack and the valve opening form the opening and closing states.

The valve provided in the example of the invention comprises a drive device; there are vents arranged on the sensing chamber of the drive device; meanwhile, the vents are located above the sensing chamber; the sundries gas enters the sensing chamber along with the working medium; the sundries gas with little density is located above and the working medium is located below the chamber; and thus, the above vents can be easier to discharge the air in the sensing chamber to keep the work stability of the valve.

On one hand, the vents are connected with bulkhead or air exhausting valve to realize the discharging manually. It is shown specifically that when the valve works, the bulkhead or air exhausting valve can be regularly opened to discharge the air retained in the sensing chamber.

On the other hand, the vent is connected with the second connecting pipeline; the other end of the second connecting pipeline is connected with the main pipeline, which benefits the automatic circulation of the working medium; the air mixed in the working medium of the sensing medium is discharged to the main pipeline to achieve the discharging effect and form the automatic circulation passage of the working medium in the valve; it can achieve the function of discharging automatically and further stabilizes the pressure of the working medium.

DESCRIPTION OF FIGURES

FIG. 1 is the sketch map of the valve comprising the drive device in the prior art.

FIG. 2 is the sketch map of the valve comprising the drive device in one of the examples.

FIG. 3 is the sketch map of the inverted valve provided in one of the examples.

FIG. 4 is the sketch map of the other valve provided in one of the examples.

FIG. 5 is the sketch map of the other valve provided in one of the examples.

FIG. 6 is the sketch map of the other valve provided in one of the examples.

FIG. 7 is the sketch map of the other inverted valve provided in one of the examples.

SPECIFIC MODE FOR CARRYING OUT THE INVENTION

The technical scheme of the invention is described further by the following drawings and the specific examples.

Example 1

The invention provides a specific example of the drive device; and the drive device is used for sensing the pressure of the working medium flowing through the drive device. The drive device comprises specifically a sensing part and a drive shaft; the sensing part is used for sensing the pressure of the working medium and generating the drive force by the drive shaft. The sensing part comprises specifically a chamber and a sensing device; the sensing device is connected with the drive shaft; due to the working medium is connected with the chamber and enters the chamber; the sensing device can sense the pressure of the working medium in the sensing chamber; the drive shaft is driven to move according to the pressure of the working medium; there are vents on the chamber of the drive device; and the air entering the chamber of the drive device along the working medium can be discharged. Specifically, the vent is connected with the air exhausting device which can be the exhausting pipeline or valve.

In addition, the drive device can be used for the adjusting valve or control valve, but not limited to this.

When the drive device is used for the adjusting valve, the sensing device of the sensing part of the drive device is a membrane, which can form the chamber of the sensing device by the membrane and the shell directly; the chamber can sense the pressure of the working medium directly and drive the drive shaft by the membrane further. Specifically, the chamber is formed by the shell and the membrane. The membrane is connected with the drive shaft; the membrane can sense the pressure in the chamber and drive the drive shaft. Due to sensing the pressure, the chamber is sealed; when the air in the working medium enters the chamber, the air is separated from the working medium and located above the working medium. There are vents above the chamber, the vents can be arranged on the shell specifically; and the air above the chamber can be discharged out of the device by the vents.

When the drive device is used for the control valve, the drive device can be the driver composed of other electronic sensing element, which comprises the chamber, sensing device and drive shaft; the sensing device can sense the pressure of the working medium charged in the chamber and be delivered to the drive shaft by the electric signal to drive the drive shaft to perform the related operation. During the process, the vents above the chamber can discharge the air mixed in the working medium out of the chamber to keep the stable drive device and the control valve comprising the drive device.

Example 2

The invention provides the specific example of the valve; and the valve comprises the drive device in example 1. Specifically, as shown in FIG. 2, the valve 2 is connected with the main fluid pipeline 3 and capable of controlling the pressure of the working medium in the main pipeline. The valve 2 comprises a drive device 20, a valve body 22 and an adjusting device 23; and the working medium is liquid fluid.

The drive device 20 comprises a sensing chamber 201 and a drive shaft 202; the sensing chamber 201 is composed of the membrane 203 and the shell 204. When the valve is in the working state, the working medium flows in the sensing chamber 201; the membrane 203 can sense the pressure of the working medium and move according to the pressure of the working medium in the sensing chamber 201; the membrane 203 is connected with one end of the drive shaft 202; when membrane 203 moves according to the pressure in the sensing chamber, the drive shaft 202 moves correspondingly along with the movement of the membrane.

The valve body 22 comprises an inlet chamber 220 and an outlet chamber 221 as well as a valve opening 222 located between the inlet chamber 220 and the outlet chamber 221 of the valve body. The inlet chamber 220 is connected with the upstream pipeline 31 of the main pipeline; the outlet chamber 221 is connected with the downstream pipeline 32 of the main pipeline; a flow control device 24 is arranged between the outlet chamber and the inlet chamber to control the flow of the working medium in the valve; the flow control device 24 is connected with one end of the drive shaft 202; it can be the valve clack connected with one end of the drive shaft; and the valve clack matches with the valve opening 222 to form the opening and closing states between the inlet chamber and the outlet chamber.

Specifically, when the amount of the working medium of the downstream 32 of the main pipeline is increased, the pressure of the sensing chamber 201 is decreased, so that the membrane 203 drives the valve clack 24 to move downwards under the action force of the adjusting device 23; the opening of the valve clack 24 and the valve opening 222 is enlarged; the flow of the working medium flowing through the upstream pipeline 31 of the main pipeline is increased; and the pressure of the outlet chamber is raised to maintain the constant downstream pressure of the main pipeline. Reversely, when the amount of the working medium of the main pipeline downstream 32 is decreased, the pressure of the sensing chamber 201 is raised, so that the membrane 203 drives the valve clack 24 to move upwards under the action force of the adjusting device 23; the opening of the valve clack 24 and the valve opening 222 is decreased; the flow of the working medium flowing through the upstream pipeline 31 of the main pipeline is decreased; and the pressure of the downstream pipeline 32 of the main pipeline is constant.

The adjusting device 23 is used for presetting the standard pressure of the working medium at the downstream pipeline of the main pipeline of the valve; when the membrane moves along the pressure of the working medium in the sensing chamber 201, the adjusting device 23 can generate a relative force according to the moving range of the membrane 203; on one hand, it can buffer the moving range of the membrane; on the other hand, the pressure of the working medium at the downstream pipeline of the main pipeline can be kept in the preset pressure value. Specifically, the drive shaft 202 drives the flow control device 24 to match with the valve opening 222, so that the flow flux of the working medium between the inlet chamber 220 and the outlet chamber 221 is kept in the stable range; and finally the pressure of the working medium flowing in the downstream pipeline of the main pipeline is kept in the preset standard pressure.

The valve in the example is provided with a first connecting pipeline 25 and a second connecting pipeline 26; there are vents 261 on the shell of the sensing chamber of the valve; specifically, one end of the first connecting pipeline 25 is arranged on the shell 204 of the drive device 20; the connecting opening with the shell is the first interface 251; the other end of the first connecting pipeline is provided with a second interface 252; one end of the second connecting pipeline 26 is connected with the vents 261; the other end of the second connecting pipeline is the third interface 262; the vents 261 on the shell are located above the first interface 251; the pressure of the working medium at the third interface 262 is less than that of the working medium at the second interface 252.

The second interface 252 of the first connecting pipeline 25 can be arranged on the downstream pipeline 32 or upstream pipeline 31 of the main pipeline or inlet chamber 220 or outlet chamber 221 of the valve. Wherever the second interface 252 of the second connecting pipeline is or whatever the valve is installed forward, backwards or side on the main pipeline, the pressure of the working medium at the second interface 252 is greater than that of the working medium at the second interface 262 of the second connecting pipeline 26; meanwhile, the first connecting pipeline 25 is arranged above the first interface 251 of the shell 204 in the vertical direction and always below the vent 261 of the shell 204.

Preferably, as shown in FIG. 2, the first connecting pipeline is arranged between the shell and the downstream pipeline of the main pipeline, namely, the first interface 251 is located on the shell of the sensing chamber; and the second interface 252 is located on the downstream pipeline of the main pipeline. When the working medium flows into the inlet chamber 220 from the upstream pipeline 31 of the main pipeline and flows into the downstream pipeline 32 of the main pipeline by the valve opening 222 and the outlet chamber 221, the working medium enters the sensing chamber 201 along the second interface 252, the first connecting pipeline 25 and the first interface 251; namely, the pressure of the working medium at the downstream pipeline of the main pipeline is delivered to the sensing chamber 201 of the drive device 20 by the first connecting pipeline 25; the sensing chamber 201 drives the drive shaft 202 correspondingly according to the pressure of the working medium; during the moving process, the drive shaft 202 drives the flow control device 24 at the other end; and the flowing control device 24 matches with the valve opening 222 to form the opening and closing states between the inlet chamber and the outlet chamber during the moving process.

Specifically, when the amount of the working medium of the downstream 32 of the main pipeline is increased, the pressure of the sensing chamber is decreased, so that the membrane drives the valve clack 24 to move downwards under the action force of the adjusting device 23; the opening of the valve clack 24 and the valve opening 222 is enlarged; thus the flow of the working medium flowing through the upstream pipeline 31 of the main pipeline is increased, which results the pressure of the outlet chamber 221 is raised to maintain the constant downstream pressure of the downstream pipeline 32 of the main pipeline. Reversely, when the amount of the working medium of the main pipeline downstream 32 is decreased, the pressure of the sensing chamber 201 is raised, so that the membrane 203 drives the valve clack 24 to move upwards under the action force of the adjusting device 23; the opening of the valve clack 24 and the valve opening 222 is decreased; the flow of the working medium flowing through the upstream pipeline 31 of the main pipeline is decreased; and the pressure of the downstream pipeline 32 of the main pipeline is constant.

The vents 261 on the shell are located above the first interface 251; in this way, when the air in the working medium enters the sensing chamber 201, the working medium is separated from the sundries gas which is located above the sensing chamber; the working medium is located below the sensing chamber; the vents 261 are located above the first interface 251, which benefits to discharge the sundries gas from the vent; and the working medium can flow into the downstream pipeline 32 of the main pipeline along with the first connecting pipeline. In addition, the first connecting pipeline 25 and the second connecting pipeline 26 are respectively provided with the second interface 252 and the third interface 262 on the downstream pipeline 32 of the main pipeline. In the example, the third interface 262 is located at the downstream of the second interface 251 at the downstream pipeline of the main pipeline; due to the main pipeline has pressure difference along the fluid direction, namely, the pressure of the working medium at the second interface 252 is greater than that at the third interface 262. When the working medium enters the valve from the upstream pipeline 31 of the main pipeline, it flows through the inlet chamber 220 and outlet chamber 221 and flows into the sensing chamber 201 from the second interface 252 on the downstream pipeline of the main pipeline and the first connecting pipeline 25; the pressure is further delivered in the sensing chamber, so that the drive device drives the flow control device 24; due to the vents 261 connected with the second connecting pipeline 26 are located above the first interface 251 connected with the first connecting pipeline 25 so that the air in the chamber can be further pressed and discharged from the second connecting pipeline 26 and the working medium mixed with air can flow out from the sensing chamber 201 along the vents 261, the second connecting pipeline 26 and the third interface 262 and flows to the downstream along with the working medium along the main pipeline. The sensing chamber is always a dynamic chamber by the circulation process so as to maintain the stability of the valve.

On the other hand, the valve in the example is installed on the fluid main pipeline; the valve in the example can be backwards installed on the fluid main pipeline; specifically, as shown in FIG. 3, the adjusting device 23 and the drive device are located below the valve body 22; the second interface 252 of the first connecting pipeline 25 on the downstream pipeline of the main pipeline is located at the upstream of the third interface 262 of the second connecting pipeline 26 and the main pipeline; meanwhile, the vents 261 connecting the second connecting pipeline 26 is located above the first interface 251 of the shell connecting with the first connecting pipeline 25 in the vertical direction, so that the gas above the sensing chamber can be discharged out from the chamber. In addition, the example limits the position of the shell in the vertical direction; on this base, it can be any position of the circumference surface on the shell over the second interface in the level direction.

When the second interface of the first connecting pipeline is arranged at the upstream pipeline of the main pipeline, as shown in FIG. 4, the third interface 262 of the second connecting pipeline 26 can be arranged at the upstream pipeline of the main pipeline; meanwhile, the second interface 252 is located at the upstream of the third interface 262 so that the pressure of the working medium at the second interface 252 is greater than that of the working medium at the third interface 262. The working medium of the upstream pipeline of the main pipeline flows into the sensing chamber 201 through the second interface 252, the first connecting pipeline 25 and the first interface 251; the medium pressure is delivered to the sensing chamber; after the air in the working medium enters the sensing chamber, it is separated from the working medium because of different densities; it is located above the sensing chamber; due to the vents 261 are designed above the first interface 251, so that the air can be discharged out from the sensing chamber and pass through the valve along with the second connecting pipeline 26 and flow to the downstream pipeline 32 of the main pipeline.

In addition, when the second interface of the first connecting pipeline is arranged at the upstream pipeline of the main pipeline, the third interface of the second connecting pipeline can be arranged at the low-voltage area in the inlet chamber; what to be attended is that the pressure of the working medium at the second interface is greater than that of the working medium at the third interface; and the vents are located above the first interface.

When the second interface 252 of the first connecting pipeline 25 is arranged at the inlet chamber 220 of the valve, the third interface 262 of the second connecting pipeline 26 can be arranged at the inlet chamber 220 of the valve; the third interface 262 is located in the low-voltage area in the inlet chamber 220; and the second interface 252 is arranged in the high-voltage area in the inlet chamber 220.

Similarly, when the second interface 252 of the first connecting pipeline 25 is arranged on the outlet chamber 221 of the valve, the third interface 262 of the second connecting pipeline 26 can be arranged on the outlet chamber 221 of the valve; the third interface 262 is located in the low-voltage area in the outlet chamber 221; the second interface 252 is located in the high-voltage area in the outlet chamber 221; the third interface 262 of the second connecting pipeline 26 can be arranged on the downstream pipeline 32 of the main pipeline; it can ensure that the pressure of the working medium of the second connecting pipeline at the third interface is less than that of the working medium at the second interface. As shown in FIG. 5, the working medium can flow in the sensing chamber 201 along the first connecting pipeline 25 from the second interface 252, so that the membrane 203 can sense the pressure to adjust the opening of the flow control device 24 and the valve opening 222; and then the pressure of the working medium in the downstream pipeline 32 of the main pipeline can be controlled. When the working medium flows into the sensing chamber 201 through the first connecting pipeline 25, the membrane 203 in the sensing chamber can sense the pressure and drive the drive shaft 202; and the fluid control device 24 controls the flow of the working medium at the valve opening 222; due to the vents 261 are located above the first interface 251, the air entering the sensing chamber 201 along with the working medium can be discharged out from the sensing chamber 201 along with the above vents 261 and the second connecting pipeline 26 and the third interface 262. It avoids retaining the air in the sensing chamber 201 and ensures the working stability of the valve.

Apart from the valve forwards installed on the main pipeline, the valve in the example 1 can be backwards or side installed on the main pipeline; the pressure of the working medium at the second interface is greater than that of the working medium at the third interface of the second connecting pipeline; meanwhile, the first interface of the first connecting pipeline on the shell is in the vertical direction and is always located below the vents the second connecting pipeline on the shell.

Example 3

The example is a deformation of the valve in example 2. As shown in FIG. 6, the valve 4 is connected with the main fluid pipeline 5 to control the pressure of the working medium in the main pipeline. The valve 4 comprises a drive device 40, a valve body 42 and an adjusting device 43; and the working medium is the liquid fluid.

Similar to the example 2, the drive device 40 comprises a sensing chamber 401 and a drive shaft 402; and the sensing chamber 401 is composed of the membrane 403 and the shell 404. When the valve is in the working state, the working medium flows in the sensing chamber 401; the membrane 403 can sense the pressure of the working medium and move according to the pressure of the working medium in the sensing chamber 401; the membrane 403 is connected with one end of the drive shaft 402; when the membrane 403 moves according to the pressure in the sensing chamber, the drive shaft 402 moves correspondingly along with the movement of the membrane.

The valve body 42 comprises an inlet chamber 420 and an outlet chamber 421 as well as a valve opening 422 between the inlet chamber 420 and the outlet chamber 421. The inlet chamber 420 is connected with the upstream pipeline 51 of the main pipeline; the outlet chamber 421 is connected with the downstream pipeline 52 of the main pipeline; the flow control device 44 is arranged between the outlet chamber and the inlet chamber to control the flow of the working medium in the valve; the flow control device 44 is connected with one end of the drive shaft 402; it specifically can be the valve clack connected with one end of the drive shaft; and the valve clack matches with the valve opening to form the opening and closing states between the inlet chamber and the outlet chamber.

The adjusting device 43 is used for presetting the standard pressure of the working medium at the downstream pipeline of the main pipeline; when the membrane moves up and down along with the pressure of the working medium in the sensing chamber 401, the adjusting device 43 can generate a relative force according to the moving range of the membrane 403; on one hand, it can buffer the moving range of the membrane; on the other hand, the pressure of the working medium at the downstream pipeline of the main pipeline can be kept in the preset pressure value. Specifically, the drive shaft 402 drives the flow control device to match with the valve opening, so that the flow flux of the working medium between the inlet chamber and the outlet chamber is kept in the steady range; and the pressure of the working medium flowing into the downstream pipeline of the main pipeline is kept in the preset standard pressure.

The valve of the example is further provided with a first connecting pipeline 45 which is arranged between the shell 404 and the downstream pipeline 52 of the main pipeline; a first interface 451 is arranged on the shell 404; and a second interface 452 is arranged on the downstream pipeline 52 of the main pipeline. When the working medium flows into the inlet chamber 420 from the upstream pipeline 51 of the main pipeline and flows into the downstream pipeline 52 of the main pipeline by the valve opening 422 and the outlet chamber 421, the working medium enters the sensing chamber 401 along the second interface 452, the first connecting pipeline 45 and the first interface 451, namely, the pressure of the working medium at the downstream pipeline 52 of the main pipeline is delivered to the sensing chamber 401 of the drive device 40 by the first connecting pipeline 45; the sensing chamber 401 can drive the drive shaft 402 correspondingly according to the pressure of the working medium; the drive shaft 402 can drive the flow control device 44 at the other end during the moving process; and the flow control device 44 matches with the valve opening 422 during the moving process to form the opening and closing states between the inlet chamber and the outlet chamber.

Specifically, when the working medium of the downstream pipeline of the main pipeline is increased, the pressure of the sensing chamber is decreased, so that the membrane drives the valve clack to move downwards under the action force of the adjusting device; the opening of the valve clack and the valve opening is enlarged, so that the flow of the working medium flowing through the upstream pipeline of the main pipeline is increased; and the pressure of the outlet chamber is raised to maintain the constant downstream pressure of the main pipeline. Reversely, when the amount of the working medium of the main pipeline downstream is decreased, the pressure of the sensing chamber is raised, so that the membrane drives the valve clack to move upwards under the action force of the adjusting device; the opening of the valve clack and the valve opening is decreased, so that the flow of the working medium flowing through the upstream pipeline of the main pipeline is decreased; and the pressure of the downstream pipeline of the main pipeline is constant.

According to the valve in the example, the valve further comprises an air exhausting device 46 which is used for discharging the air in the sensing chamber; specifically, the air exhausting device 46 is connected with the vents 461 on the shell; and the vents 461 are located above the first interface 451 of the first connecting pipeline 45; when the working medium mixed with the air enters the sensing chamber 401 along the first connecting pipeline 45, the mixed air is above the working medium of the sensing chamber; when the air in the sensing chamber 401 accumulates to a certain degree, the valve is unstable; thus the air exhausting device on the vents can be regularly opened; the air in the sensing chamber is discharged out of the sensing chamber; when the working medium in the air exhausting device is discharged, it shows that the gas in the sensing chamber has been discharged; at this time, the air exhausting device is closed; and the valve can operate normally and steadily.

The air exhausting device in the example is a bulkhead, such as end cap and the like.

The air exhausting device in the example can be the vent valve, such as ball valve, single valve, etc.

Similar to the example 2, the first connecting pipeline 45 can be arranged on the shell and the outlet chamber; the working medium can flow into the sensing chamber along the first connecting pipeline from the outlet chamber, so that the membrane can sense the pressure to adjust the opening of the flow control device and the valve opening; and then the pressure of the working medium at the downstream pipeline of the main pipeline can be controlled.

Similar to the example 2, the valve can be backwards installed on the main fluid pipeline, as shown in FIG. 7; the adjusting device 43 and the drive device are located below the valve body 42; the vents 461 connected with the air exhausting device 46 are located above the first interface 451 of the first connecting pipeline 45 on the shell in the vertical direction, so that the gas above the sensing chamber can be discharged out from the chamber. In addition, the example limits the position of the shell in the vertical direction only; and on this basis, it can be any position of the interface on the shell in the level direction.

The valve protected in the invention can be voltage regulator, backpressure valve or control valve of which the pressure can be sensed and adjusted by other electronic sensing elements, and it is not limited by the above valve.

It needs to be stated that, in the text, terms “comprising(comprise)” or other variants are intended to cover nonexclusive comprising, so that the process, method, article or device which comprises a series of elements not only comprise such element, but also further comprises other elements which are not clearly listed, or intrinsic elements of the process, method, article or device. Under the situation of no more limitations, elements defined by a phrase “comprising one . . . ” do not exclude other same elements in the process, method, article or device which comprises the elements.

Although terms such as first, second and third can be used to describe various components, parts or portions, these components, parts or portions shall not be limited by these terms; and these terms are only used for distinguishing a component, part or portion. When numerical value terms such as “first” and “second” are used herein, they do not contain sequences or orders, unless otherwise clearly stated in the context. Therefore, under the situation of not departing from the description of the exemplary examples, the first component, part or portion described below can be explained as the term of a first component, part or portion.

The above examples are the better examples of the invention which do not limit the protection range of the invention. Any modification, same replacement, improvement and the like in the spirit and principle of the invention are included in the protection range of the invention. 

1. A drive device, which can sense the pressure of the working medium and generate drive force, characterized in that the drive device comprises: a sensing part, which comprises a chamber and a sensing device located in or above the chamber; there are vents on the chamber, a drive shaft which passes through the chamber; one end of the drive shaft is connected with the sensing device; the sensing device can sense the pressure of the working medium and drive the drive shaft to move.
 2. The drive device according to claim 1, characterized in that the chamber comprises a shell and a membrane; the membrane is the sensing device which is connected with the drive shaft; the working medium communicates with the shell and enters the chamber; the membrane senses the pressure change of the working medium and drives the drive shaft to move.
 3. A valve, which is connected with the main fluid pipeline and adjusts the pressure in the main pipeline, characterized in that the valve comprises a drive device and a valve, the drive device is connected with the valve; the valve comprises an inlet chamber and an outlet chamber; the inlet chamber is connected with the upstream pipeline of the main pipeline; the outlet chamber is connected with the downstream pipeline of the main pipeline; the flow control device is arranged between the inlet chamber and outlet chamber; the flow control device controls the flow of the working medium in the control valve; the drive device comprises a sensing chamber and a drive shaft; the sensing chamber is composed of a membrane and a shell; the membrane is connected with one end of the drive shaft and capable of sensing the pressure in the sensing chamber and driving the drive shaft to move; there are vents on the shell; and the other end of the drive shaft of the drive device is connected with the flow control device.
 4. The valve according to claim 3, characterized in that a first connecting pipeline is arranged on the shell of the sensing chamber; and the vents are located above the connection position of the first connecting pipeline and the shell in the vertical direction.
 5. The valve according to claim 4, characterized in that the first connecting pipe is arranged between the shell and the downstream pipeline of the main pipeline; a second connecting pipeline is arranged between the vents and the downstream pipeline of the main pipeline; and the connection position of the second connecting pipeline and the downstream pipeline of the main pipeline is located at the downstream of the connecting position of the first connecting pipeline and the downstream pipeline of the main pipeline.
 6. The valve according to claim 4, characterized in that the first connecting pipeline is arranged between the shell and the upstream pipeline of the main pipeline; a second connecting pipeline is arranged between the vents and the upstream pipeline of the main pipeline; and the connecting position of the second connecting pipeline and the upstream pipeline of the main pipeline is located at the downstream of the connecting position of the first connecting pipeline and the upstream pipeline of the main pipeline.
 7. The valve according to claim 4, characterized in that the vents are connected with the air exhausting device; and the air exhausting device controls the gas exhausted from the sensing chamber.
 8. The valve according to claim 7, characterized in that the air exhausting device is the bulkhead or vent valve.
 9. The valve according to claim 3, characterized in that the flow control device is the valve clack which is arranged at the end of the drive shaft; the valve further comprises a valve opening arranged in the valve; the valve opening is arranged between the inlet chamber and the outlet chamber; the valve clack matches with the valve opening; the valve clack and the valve opening form the opening and closing states along with the movement of the drive shaft. 